My idle will drop spontaneously after driving to the point of dying, and just recently my heater will only blow cold air while i'm driving and even after it warms up if i stop at a light or stop accelerating for any reason it will blow cold air again? the power surges have been happening for quite some time but i've had this car for 2 years and last winter the heater worked fine...but im sure they're connected somehow because when my rpms drop so does the heat in the vehicle? help?